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IQueueCallbackDeviceIoControl::OnDeviceIoControl method (wudfddi.h)

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Warning

UMDF 2 is the latest version of UMDF and supersedes UMDF 1. All new UMDF drivers should be written using UMDF 2. No new features are being added to UMDF 1 and there is limited support for UMDF 1 on newer versions of Windows 10. Universal Windows drivers must use UMDF 2. For more info, see Getting Started with UMDF.

The OnDeviceIoControl method is called to handle a device I/O control request when an application performs a specific operation on a device through the Microsoft Win32 OnDeviceIoControl function.

Syntax

void OnDeviceIoControl(
  [in] IWDFIoQueue   *pWdfQueue,
  [in] IWDFIoRequest *pWdfRequest,
  [in] ULONG         ControlCode,
       SIZE_T        InputBufferSizeInBytes,
       SIZE_T        OutputBufferSizeInBytes
);

Parameters

[in] pWdfQueue

A pointer to the IWDFIoQueue interface for the I/O queue object that the request arrives from.

[in] pWdfRequest

A pointer to the IWDFIoRequest interface that represents the framework request object.

[in] ControlCode

The driver-defined or system-defined I/O control code (IOCTL) that identifies the specific operation to be performed and that is associated with the request.

InputBufferSizeInBytes

The size, in bytes, of the input buffer for the request.

OutputBufferSizeInBytes

The size, in bytes, of the output buffer for the request.

Return value

None

Remarks

A driver registers the IQueueCallbackDeviceIoControl interface when the driver calls the IWDFDevice::CreateIoQueue method to create an I/O queue or to configure the default I/O queue.

A driver can implement a single OnDeviceIoControl method for all I/O queues or separate OnDeviceIoControl methods for each I/O queue.

The OnDeviceIoControl method receives every device I/O control request type from a queue. (The request type is identified by the WdfRequestDeviceIoControl value of the WDF_REQUEST_TYPE enumeration type for the request.)

For more information about the driver's methods that are associated with queues and that the framework calls, see I/O Queue Event Callback Functions. The OnDeviceIoControl method must process each received device I/O control request. For more information about how UMDF drivers process I/O requests, see Processing I/O Requests.

The driver can call the IWDFIoRequest::GetDeviceIoControlParameters, IWDFIoRequest::GetInputMemory, and IWDFIoRequest::GetOutputMemory methods to retrieve information about the request and the input and output buffers.

Requirements

Requirement Value
Target Platform Windows
Header wudfddi.h (include Wudfddi.h)

See also